/* Copyright 2007,2010,2012,2018 IPB, Universite de Bordeaux, INRIA & CNRS
**
** This file is part of the Scotch software package for static mapping,
** graph partitioning and sparse matrix ordering.
**
** This software is governed by the CeCILL-C license under French law
** and abiding by the rules of distribution of free software. You can
** use, modify and/or redistribute the software under the terms of the
** CeCILL-C license as circulated by CEA, CNRS and INRIA at the following
** URL: "http://www.cecill.info".
** 
** As a counterpart to the access to the source code and rights to copy,
** modify and redistribute granted by the license, users are provided
** only with a limited warranty and the software's author, the holder of
** the economic rights, and the successive licensors have only limited
** liability.
** 
** In this respect, the user's attention is drawn to the risks associated
** with loading, using, modifying and/or developing or reproducing the
** software by the user in light of its specific status of free software,
** that may mean that it is complicated to manipulate, and that also
** therefore means that it is reserved for developers and experienced
** professionals having in-depth computer knowledge. Users are therefore
** encouraged to load and test the software's suitability as regards
** their requirements in conditions enabling the security of their
** systems and/or data to be ensured and, more generally, to use and
** operate it in the same conditions as regards security.
** 
** The fact that you are presently reading this means that you have had
** knowledge of the CeCILL-C license and that you accept its terms.
*/
/************************************************************/
/**                                                        **/
/**   NAME       : library_dgraph_io_load_f.c              **/
/**                                                        **/
/**   AUTHOR     : Francois PELLEGRINI                     **/
/**                                                        **/
/**   FUNCTION   : This file contains the Fortran API for  **/
/**                the distributed source graph handling   **/
/**                routines of the libSCOTCH library.      **/
/**                                                        **/
/**   DATES      : # Version 5.0  : from : 13 may 2007     **/
/**                                 to     13 may 2007     **/
/**                # Version 5.1  : from : 27 mar 2010     **/
/**                                 to     27 mar 2010     **/
/**                # Version 6.0  : from : 29 nov 2012     **/
/**                                 to     25 apr 2018     **/
/**                                                        **/
/************************************************************/

/*
**  The defines and includes.
*/

#define LIBRARY

#include "module.h"
#include "common.h"
#include "ptscotch.h"

/**************************************/
/*                                    */
/* These routines are the Fortran API */
/* for the graph handling routines.   */
/*                                    */
/**************************************/

/* When an input stream is built from the given
** file handle, it is set as unbuffered, so as to
** allow for multiple stream reads from the same
** file handle. If it were buffered, too many
** input characters would be read on the first
** block read.
*/

SCOTCH_FORTRAN (                      \
DGRAPHLOAD, dgraphload, (             \
SCOTCH_Dgraph * const       grafptr,  \
int * const                 fileptr,  \
const SCOTCH_Num * const    baseval,  \
const SCOTCH_Num * const    flagval,  \
int * const                 revaptr), \
(grafptr, fileptr, baseval, flagval, revaptr))
{
  FILE *              stream;                     /* Stream to build from handle */
  int                 filenum;                    /* Duplicated handle           */
  int                 o;

  if (*fileptr == -1)                             /* If process does not want to open a stream */
    stream = NULL;
  else {
    if ((filenum = dup (*fileptr)) < 0) {         /* If cannot duplicate file descriptor */
      errorPrint (STRINGIFY (SCOTCH_NAME_PUBLICFU (DGRAPHLOAD)) ": cannot duplicate handle");
      *revaptr = 1;                               /* Indicate error */
      return;
    }
    if ((stream = fdopen (filenum, "r")) == NULL) { /* Build stream from handle */
      errorPrint (STRINGIFY (SCOTCH_NAME_PUBLICFU (DGRAPHLOAD)) ": cannot open input stream");
      close      (filenum);
      *revaptr = 1;
      return;
    }
    setbuf (stream, NULL);                        /* Do not buffer on input */
  }

  o = SCOTCH_dgraphLoad (grafptr, stream, *baseval, *flagval);

  if (stream != NULL)                             /* If process has an open stream */
    fclose (stream);                              /* This closes filenum too       */

  *revaptr = o;
}
